1. Technical Field
The disclosure relates to a manufacturing method of a grating.
2. Description of Related Art
A sub-wavelength grating is a common optical component in the semiconductor industry. The size of the sub-wavelength grating is similar to or less than the active wavelength of the sub-wavelength grating. It is difficult to make a quartz grating with high density, sub-wavelength, and mark-space ratio. The sub-wavelength grating may be made by electron beam lithography, focused ion beam lithography, deep-ultraviolet lithography, holographic lithography, and nano-imprint lithography.
In the prior art, the aspect ratio of the sub-wavelength grating is 1:1 so as to limit the application field.